Creating Accessible Digital Multimedia

Creating Accessible Web Sites | Creating Accessible Digital Multimedia
Creating Accessible Analog & Print Media

An accessible digital multimedia presentation should always contain the following features:

• Captions, which provide a textual equivalent for all audio
• Audio descriptions, which describe important visual elements of the presentation
• A transcript, so braille users can read the contents of the presentation, and so anyone can scan the contents of a presentation prior to viewing it

There are two digital multimedia formats that support the inclusion of audio descriptions and closed captions in digital multimedia presentations: Synchronized Multimedia Integration Language (SMIL) and Synchronized Accessible Media Interchange (SAMI).

SMIL (www.w3.org/AudioVideo/) is played by the QuickTime Player (www.apple.com/quicktime) versions 4.1.2 and later, RealPlayer (www.real.com) versions G2 and later, and the Oratrix GRiNS Player (www.oratrix.com).

SAMI (msdn.microsoft.com/library/default.asp? url=/library/en-us/dnacc/html/atg_samiarticle.asp) is played by Windows Media Player (www.microsoft.com/windows/windowsmedia/default.asp) only and supports closed captions but not audio descriptions.

For examples of accessible multimedia in several different formats, visit the Rich Media Resource Center at the CPB/WGBH National Center for Accessible Media (NCAM) (ncam.wgbh.org/richmedia/).

Captions and audio descriptions can be added to digital multimedia using the Media Access Generator (MAGpie), a free utility provided by NCAM. Copies for the PC or Macintosh (OS X and higher) may be downloaded from ncam.wgbh.org/webaccess/magpie/. Transcripts, which are an inherent part of the captioning process, can also be created with MAGpie. MAGpie cannot be used for analog media.

Finally, the convergence of television, computer, and Internet technologies is presenting its own unique accessibility challenges. Industry is currently developing methods to address these problems; more information can be found at NCAM's Access to Convergent Media project at ncam.wgbh.org/convergence/. General information about barriers to convergent media for individuals who are blind or have low vision can also be found at ncam.wgbh.org/convergence/barriers.html. Additionally, NCAM will publish guidelines relating to creating accessible convergent media, including DVDs with talking menus, in early 2003.